environment: input
000: 00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00   |                |
010: 00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 09   |                |
environment: key
000: 55 55 55 55 55 55 55 55  55 55 55 55 55 55 55 55   |UUUUUUUUUUUUUUUU|
010: 55 55 55 55 55 55 55 55  55 55 55 55 55 55 55 55   |UUUUUUUUUUUUUUUU|

curve25519: output
000: 7f 42 1b f9 34 5a 59 84  4a 30 bc 53 64 74 fa 7c   | B  4ZY J0 Sdt ||
010: 15 81 77 a4 4d 34 6d 2f  8b c1 8c 05 d6 a9 44 54   |  w M4m/      DT|